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Review: Boston Venom Epyc (pre-production unit)

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Published: 30 January 2018

With dual 32-core AMD Epyc CPUs, this beast of a machine from Boston offers an incredible proposition for rendering – but at the expense of single-threaded performance, writes Greg Corke

AMD’s resurgence in the CPU sector may be characterised by its Ryzen and Threadripper processors but, when it comes to multi-threaded brute force, it’s the lesser known Epyc CPU that wins hands down. With up to 32 cores (and 64 threads) per CPU and two CPUs per machine, it promises the kind of processing power that most digital artists can only dream of.

AMD Epyc is primarily designed for servers and datacentres. However, because of the sheer number of cores it’s also starting to make its way into workstations.

We got our hands on a pre-production version of the Boston Venom Epyc, which was configured with dual AMD Epyc 7551 CPUs. With 32 cores in each processor, it has massive potential for multi-threaded workflows. However, to get this kind of core density in a 180W chip, there’s a trade off in frequency and the CPU runs at a base of 2.0GHz, with an all core boost speed of 2.55GHz and a max turbo of 3.0GHz.

We first tested the machine in a workflow where it was destined to excel. Right on cue, it delivered our Luxion KeyShot render in a phenomenal 95 seconds, just a second slower than the dual Intel Xeon Gold 6154 Armari R80 workstation. It also completed the V-Ray benchmark in 21 seconds, which puts it in the top ten highest scores on the public chart.

During these short tests, we observed the CPU frequency stayed close to the ‘all core boost speed’ of 2.55GHz. But those who invest in a machine like this rarely let it go idle for long and during sustained renders, the frequency dropped to 2.3GHz.

Of course, workstations also need to perform single-threaded operations, which is important for general modelling and system performance.

Even with the CPU operating at 3.0GHz, it came bottom in our SolidWorks IGES model export test and was 47% slower than the Armari R80 with two Intel Xeon Gold 6154 CPUs clocked at 3.7GHz.

Graphics performance can also be influenced by the clock speed of the CPU, but this depends on the nature of the application. 3D performance in CAD software, for example, is very much influenced by CPU frequency, so it came as no surprise that the AMD Radeon Pro WX 7100 delivered significantly slower performance than when the same GPU is in a workstation with a higher frequency CPU.

In our game engine viz and VR benchmarks, however, there was much less slow-down and, in some cases, none at all. In these applications, the GPU is the main bottleneck, so the frequency of the CPU becomes less important.

For those who need more GPU power for real-time viz, GPU rendering or GPU accelerated video editing, for example, the machine can support two double-height graphics cards on its Supermicro H11DSi-NT motherboard, such as the AMD Radeon Pro WX 9100.

Considering that one of the big features of AMD’s Epyc architecture is that it has 128 PCIe lanes (compared to 48 on Intel Xeon Scalable), support for two GPUs on this system seems quite miserly. Of course, this is a moot point if your workflow won’t benefit from multiple GPUs, but theoretically, you could have an Epyc workstation with six or even eight x16 PCIe graphics cards.

If you do need more, the Venom Epyc can actually support up to 2TB. This could be particularly relevant if using the machine to solve colossal simulation studies in Computational Fluid Dynamics (CFD) software. In memory-hungry applications like this, the 8-channel DDR4 controller (which theoretically offers more memory bandwidth than the six channel Intel Xeon Scalable) could also offer additional benefits.

With the kind of computational power you’d typically expect to find in a server, you might not be surprised to learn that the Boston Venom Epyc essentially is one. Based on the Supermicro AS-4023S-TRT server chassis, the machine can be both tower or 4U rack mounted. It also comes with many server-grade features such as a 1,280W Redundant (1+1) PSU (so if one unit fails it keeps going), integrated IPMI 2.0 for remote management, and dual 10G LAN ports. The machine even came configured with Windows Server 2016, which we are told is popular with film studios, but was incompatible with some of our 3D CAD benchmarks.

Another server-grade feature is the 8 hot-swap 3.5” SATA3 drive bays (optional SAS 12Gb and U.2 NVMe) that are easily accessible from the front of the heavy-duty chassis, one of which housed a 240GB Intel SSD. Operating system and applications, however, were loaded on a 512GB Samsung 960 Pro NVMe SSD, populating the only M.2 slot on the motherboard.

There is a downside to the machine’s server heritage and that is the Venom Epyc is also very noisy. Fans run at a high RPM even when idle. However, Boston did say it is looking to use lower dB fans in the production version.

Conclusion

If you are a digital artist with an extremely demanding rendering workflow, having this level of multi-threaded performance allows you to completely change the way you work. It can mean more iterations, higher-quality results or simply getting your renders back quicker.

This is all fine if you have this resource in a server, as multi-threaded performance is the only thing you care about. However, in a workstation, you have to accept it will impact performance in single-threaded workflows. While the Boston Venom Epyc felt responsive, general system performance will be slower than most workstations and you will always wait longer for results from single-threaded calculations.

AMD does have some other Epyc CPUs at different price points, such as the AMD Epyc 7601 (32 cores, 2.2GHz base and 3.2GHz Turbo) or the AMD Epyc 7451 (24 cores, 2.3GHz base and 3.2GHz Turbo). But when it comes to design viz on the desktop, it will be hard to beat an Intel Xeon Gold workstation. The Intel Xeon Gold 6154, for example, not only delivers similar rendering speeds, but with a better balance of cores and frequency, superior performance in single-threaded workflows.

It could be a different story when it comes to simulation. With 32 cores and bundles of high-bandwidth 8-channel memory, you may see a benefit when running multiple FEA or CFD calculations on a single machine. And with Intel Xeon Scalable only going up to 28 cores and chips costing over $10,000, the Epyc can’t be beaten on price per core.